Return to menu, at least in my experience, means it has not found the boot.dol at the location specified in the forwarder's code.
I would check where these forwarders actually look for the boot.dol.
e.g. My usbloader forwarder looks in sd:\apps\usbloader. If I changed the name to sd:\apps\usbloader1.5 then the forwarder would fail.
Or it could be something else.